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    <title>标签指定式选择器的应用</title>
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<p> 普通的文本</p>
<p class="p">品牌萨克加大了开始</p>
<h3 class="red">撒大苏打三大势力的卡死了</h3>
<p><strong>后代强调</strong></p>
<strong>嵌套之外由strong标签定义的文本（蓝色）.</strong>
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